Type of fixation is not associated with range of motion after operative treatment of proximal radius fractures- a systematic review of 519 patients

Background The aims of this study are 1) to assess whether open reduction internal fixation (ORIF) techniques for fractures of the proximal radius are associated with the range of motion (ROM), 2) to determine the incidence of hardware-related complications and removal following plate and screw fixation of the proximal radius, and 3) to evaluate whether the safe-zone definition is described in the literature and its relation to the ROM. Methods A literature search was performed in the PubMed, Embase, and Cochrane databases. Studies reporting ROM in patients undergoing ORIF for radial head or neck fractures were included. Two treatment groups were defined based on ORIF technique: screws only or plates with and without additional screw placement. Results A total of 13 articles were included with 519 patients, of which 271 belonged to the screw group and 248 to the plate group. At final follow-up, the screw group reported a mean supination of 79 (95% CI: 74-83), pronation of 76 (95% CI: 69-84), flexion of 131 (95% CI: 124-138), and loss of extension of 4 (95% CI: 1-7). The plate group reported a mean supination of 72 (95% CI: 65-80), pronation of 697 (95% CI: 60-75), flexion of 126 (95% CI: 118-133), and loss of extension of 7 (95% CI: 1-14). Conclusion Predominantly retrospective studies show that the ROM seems similar for screw and plate osteosynthesis of proximal radius fractures. Complication rates are similar as well. The safe-zone definition is rarely reported.

outcomes. 60It is theorized that plates, in contrast to countersunk headless screws, are more likely to obstruct the radio-ulnar joint and reduce the pronation-supination arc, especially when the surgeon works outside the so-called 'safe zone'. 41This safe zone is generally described as an area where the radial head does not contact the proximal ulna during maximal pronation and supination. 48However, it is specifically this pronation-supination arc that is, required in activities of daily living (ADL).Contemporary tasks, such as using a computer keyboard, opening a door, or using a modern phone, require maximum pronation (65 ± 8 degrees), maximum supination (77 ± 13 degrees), and a maximum flexion-extension arc (142 ± 3 degrees), respectively. 43In spite of this, safe-zone definitions are rarely mentioned in studies, and plate removal is commonly seen in such cases due to hardware prominence or misplacement, causing impingement and decreasing rotations. 21,49herefore, this review aimed to (1) assess whether ORIF techniques (either screws or plating) for fractures of the proximal radius are associated with the final range of motion (ROM), especially forearm rotation, (2) provide an overview of other functional outcomes, complication rates, need for hardware removal, and revision rates following the different ORIF techniques, and (3) evaluate employed definitions of the safe zone and its relationship with ROM across the literature.

Materials and methods
This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. 37The protocol is registered at the International Prospective Register of Systematic Reviews under the number: CRD42022380380, and can be accessed electronically at: https://www.crd.york.ac.uk/prospero/.

Study inclusion and exclusion
Studies reporting ROM in patients undergoing ORIF with (headless) compression screws, neck plates, or head plates for an acute radial head or neck fracture were eligible for inclusion.Studies written in English or Dutch with at least 12 months of mean follow-up and that reported a minimum of 10 patients were included.Reviews, cadaveric studies, expert opinions, abstracts, and surgical technique articles were excluded.Articles in which concomitant fractures were mentioned that could affect elbow ROM significantly were excluded during title-abstract screening.This included ipsilateral, large coronoid fractures, capitellum fractures, olecranon fractures, distal humerus fractures, distal radius fractures, and Galeazzi fractures.A patient with an additional capitellum fracture in the study by Esser et al 14 was included in the review as the fracture did not influence ROM and the patient had satisfactory results, according to the authors.The small coronoid and capitellum avulsion fractures in the study by Model et al 32 were also considered noninfluential for ROM, and the article was thus included in the review.Patients undergoing revision surgeries were excluded as well.Studies reporting on both screw and plate fixation had to report outcomes separately for the subgroups to be included.

Literature search strategy
Relevant studies were identified by searching PubMed, Embase/ Ovid, Cochrane Database of Systematic Reviews/Wiley, Cochrane Central Register of Controlled Trials/Wiley, and Web of Science/ Clarivate from inception up to October 11th, 2023 (by N.A., R.V., and S.P.V., information specialist).The following terms, including synonyms and closely related words, were used as index terms or freetext words: 'radius', 'fracture', 'proximal', 'fixation', and 'ORIF'.Full search strategies are available as Supplementary Information in Supplementary Data IV.No filters or other restrictions were applied to any of the searches.Title, abstract, and full-text screening were performed by three independent reviewers (N.A., R.V., and H.K.) to identify potentially relevant articles by use of Rayyan. 36The authors independently selected articles.Studies were not blinded for author, affiliation, or source.Any disagreements were resolved by a fourth author (M.B.).

Quality assessment
Two reviewers (N.A. and H.K.) independently assessed each study for its risk of bias using the Cochrane risk-of-bias tool and methodological index for nonrandomized studies (MINORS). 47andomized controlled trials were assessed using the Cochrane risk-of-bias tool (version 2.0; The Cochrane Collaboration, London, UK). 20,44,50The MINORS is a validated and established index for evaluating the methodological quality of nonrandomized studies.The MINORS involves 12 criteria for comparative studies, of which eight criteria have been designed for noncomparative studies.These items are scored according to the set criteria: 0 (not reported), 1 (reported but inadequate), or 2 (reported and adequate).The MINORS score per group, meaning comparative and noncomparative studies, is displayed as a percentage of the total score.The review of Ekhtiari et al 13 introduces an interpretation of this score, where a MINORS score 5 indicated very low-quality evidence, a score of 6-9 indicated low quality of evidence, a score of 10-15 indicated fair quality of evidence, and a score 16 indicated a relatively good quality of evidence for nonrandomized studies.

Data extraction
The following parameters were recorded when available: number of patients and elbows, sex, mean age, length of follow-up, Mason fracture type, and ORIF technique.The relevant outcome parameters included primary functional outcomes (including flexion-extension ROM and pronation-supination ROM) and secondary patient-reported outcome measures (PROMs), including visual analog scale (VAS), 9 Mayo Elbow Performance Score (MEPS), 33 (quick) Disability of the Arm, Shoulder and Hand Questionnaire, 25 Oxford Elbow Score (OES), 11 and Broberg-Morrey score. 6The VAS 9 is a score to measure pain intensity postoperatively, ranging from 0 to 10, with a higher score indicating more pain.The MEPS 33 is an elbow outcome score used to test limitations in the elbow during ADL.The Broberg and Morrey 6 rating system describes four sections such as motion, strength, stability, and pain.Both scores range from 0 to 100, with a higher score indicating a superior outcome.The DASH 25 score uses 30 items to measure physical function and symptoms, whereas the quick DASH uses 11 items to measure the same symptoms.The OES 11 is a 12-item questionnaire to assess outcomes of elbow surgery based on elbow function, pain, and social-psychological results.Complication and reoperation rates were also collected.The data on the inclusion of heterotopic ossification (HO), post traumatic elbow stiffness, soft tissue injury, and elbow dislocation cases were collected.However, these data were subsequently excluded from analysis due to inconsistent reports.
Two treatment groups were defined based on the ORIF technique.One group comprised patients in whom solely screws were placed, while in the other group a plate was used.Plate variations were not taken into account, as the main goal was to assess whether plates influence the pronation-supination ROM in general terms.Indications for choice of fixation method and ORIF technique were noted when provided.
The complications were categorized as minor and major by two elbow specialists (B.K. and M.B.) based on the severity of the complications.These were in accordance with prior literature. 32,42,51,55Major complications were defined as events that seriously affect functioning in a patient's daily life, are not treatable in a timely manner, and are at least partially irreversible, such as nonunion, secondary displacement, and hardware breakage.These criteria were considered indications for reoperation according to two experienced elbow surgeons (M.B. and B.K.) and definitions aligned with the articles included in this review.All other complications were defined as minor.
For the third aim, a safe zone was identified and extracted within all studies to compare the differences.This was accomplished either by searching for a description of the safe zone based on anatomical landmarks in the section on surgical techniques or by examining the cited sources when outlining the safe zone.These cited sources were explored for safe-zone definitions.If no definition was given in the cited source, the included paper was excluded for this sub analysis.

Data and statistical analysis
The primary outcome measure was the ROM (including flexionextension and pronation-supination).Secondary outcomes were PROMs and complication rates.
The data on ROM and PROMs were pooled for the plate and screw groups separately.To enable pooling, data were transformed into means and standard deviations (SD) in case they were reported differently.When medians were reported, transformation to a mean was performed according to Hozo et al 22 In the case of reported ranges, transformation to SD was done according to Walter et al 52 and Wan et al. 53 Chi-squared test was used to compare subgroup differences for Mason types.These results were reported in the following format: X2 (degrees of freedom, N ¼ sample size) ¼ chi-square statistic value, p ¼ P value. 61Cochran's Q test was used to compare subgroup differences for complication rates.These results were reported in the following format: (X 2 ₁ (degrees of freedom) ¼ Q-test statistic value, p ¼ P value). 35ooling of the data was performed based on a random effect model with inverse variance weighting.In this review, the I 2 statistic was used to explore the level of heterogeneity among the studies.To determine the degree of heterogeneity, thresholds were maintained and categorized as follows: an I 2 of less than 25% (low heterogeneity), between 25% and 50% (moderate heterogeneity), and over 50% (high heterogeneity) following the guidelines in the Cochrane Handbook and Higgins et al. 18,19 Forest plots were created, and I 2 was calculated using the Meta package in R version 4.2.2 (R Core Team (2022).R: A language and environment for statistical computing.R Foundation for Statistical Computing, Vienna, Austria). 40

Screening and study characteristics
The search resulted in 6514 articles, and after duplicates (n ¼ 3420) were removed, 3094 articles were included for title-abstract screening.A total of 50 articles were included for full-text screening.This screening resulted in 13 included articles.The 37 studies excluded during full-text screening were excluded for the following reasons: nonretrievability (n ¼ 11), lack of ROM reports (n ¼ 8), study designed as a review (n ¼ 8), no division between subgroups (n ¼ 3), very small elbow population (n ¼ 3), no treatment (n ¼ 2), no fracture mentioned (n ¼ 1), and very short of a follow-up (n ¼ 1) (Fig. 1).These articles comprised 519 ORIF procedures in a total of 519 patients.The 271 patients in the screw group had a mean follow-up duration of 21 months, while the 248 patients in the plate group had a mean follow-up duration of 22 months. 12,14,16,17,29,30,32,34,38,45,56,57,59Within the plate group, higher Mason type fractures were observed in contrast to the screw group (X2 (4, N ¼ 519) ¼ 32.1696, P < .001)(Fig. 2).An overview of the baseline study characteristics of the included studies is displayed in Table I.

Indication for choice of technique
The choice of ORIF technique was documented when provided by the selected articles.Seven of the 13 (54%) articles 12,29,30,34,38,57,59 did not provide a justification for their selection of ORIF technique.Of the 6 articles 14,16,17,32,45,56 that described indications, two articles 14,16 utilized screws for simple fractures (Mason type II fractures) and plates for fractures with severe comminution or decapitation of the radial head (Mason type III fractures).Model et al 32 17 comminuted fractures with no more than 3 fragments, 17,45 young patients, 45 and small, intra-articular fragments that were difficult to fixate with screws or had a risk of secondary fractures. 56

Methodologic quality evaluation
An overview of the methodologic quality evaluations is presented in Supplementary Data I.The Cochrane risk-of-bias tool was used for the randomized controlled trial, resulting in some concerns of bias for Mulders et al. 34 The MINORS scores for the noncomparative and comparative studies achieved an average of 53% and 65% of the overall score, respectively.Most study designs lacked prospective collection of data (100%), prospective calculation of the study size (100%), and an adequate control group (46%).According to the score by Ekhtiari et al, 13 1 article had a low quality of evidence, 32 5 articles had a fair quality of evidence, 12,14,16,17,29 and 6 articles had a relatively good quality of evidence. 30,38,45,56,57,59M In this study, screw and plate fixation seem similar in outcome regarding ROM.The screw group reported pooled mean values for supination of 79 degrees (95% CI: 74-83), for pronation 76 degrees (95% CI: 69-84), for flexion 131 degrees (95% CI: 124-138), and for loss of extension 4 degrees (95% CI: 1-7).The plate group reported a pooled mean supination of 72 degrees (95% CI: 65-80), pronation of 67 degrees (95% CI: 60-75), flexion of 126 degrees (95% CI: 118-133), and loss of extension of 7 degrees (95% CI: 1-14).The screw group achieved sufficient ROM for ADL regarding supination (at least 77 degrees) and pronation (at least 65 degrees).43 The plate group achieved sufficient ROM for ADL regarding pronation and was just short on ROM regarding supination.Both groups lacked ROM for flexion (at least 142 degrees).43 An overview of the ROMs per study is presented in Fig. 3.

PROMs and complications
In this study, seemingly no difference was observed between screw or plate fixation regarding secondary functional outcomes.Complication rates are similar as well.Eleven studies 12,14,17,29,30,32,34,45,56,57,59 reported functional outcomes besides the ROM.MEPSs were 94 (95% CI: 91-97) and 89 (95% CI: 83-95) for screw and plate fixation, respectively (Table II).Regarding OES and VAS, no meaningful analysis could be done due to inadequate quality of data and missing values.Forest plots can be found in Supplementary Data II.

Safe-zone definition
In this study, plate fixation on the anterolateral aspect of the radial head seems to have a better outcome for supination than plates placed on the posterolateral aspect of the radial head.However, safe-zone definitions currently lack sufficient details in the literature to form a conclusive decision on the optimal placement of plates and their impact on the ROM.Within the screw group, 1 study 29 described a safe-zone definition.Of the five studies mentioning the usage of a safe zone in the plate group, 14,17,29,45,56 four of them provided a clear definition of the safe zone (Fig. 4).Guo et al 17 and Yang et al 56 described plate placement on the posterolateral aspect, from Lister's tubercle to the radial styloid.Plates placed on the posterolateral aspect of the radial head had a combined mean supination of 67 degrees (SD: 8) and a mean pronation of 68 degrees (SD: 3).Li et al 29 and Esser et al 14 described placing the screws or plates on the anterolateral aspect of the proximal radius and maximum pronation and supination were confirmed intraoperatively, but did not describe anatomical landmarks for plate placement.Plates placed on the anterolateral aspect of the radial head had a combined mean supination of 76 degrees (SD: 14) and a mean pronation of 68 degrees (SD: 16) (Table V, Fig. 4).Ma et al, 30 defined the safe zone definition as an arc spanning 41 degrees anteromedially to 69 degrees posterolaterally, with the center positioned at 166 degrees from the great prominence of the bicipital tuberosity.However, they did not provide ROMs for comparison.Instead, MEPS and DASH scores were provided.Plates positioned within the safe zone showed no differences compared to screws.Conversely, outside the safe zone, the average MEPS was notably higher in the screw groups (82 vs. 89 & 90), while the average DASH was lower in the screw groups (15 vs. 9 & 10).A more detailed description of the safe zone can be found in Supplementary Data III.

Important findings
Our study aimed to assess if elbow ROM is affected by ORIF technique (either screws or plating) for proximal radius fractures.Additionally, we assessed possible associations with other outcomes and employed safe-zone definitions.
The most important findings were that (1) although patients who underwent plate fixation had higher Mason type fractures, it seems that there are no substantial differences in terms of ROM and secondary functional outcomes compared to the screw group; (2) complication rates were similar between the two groups, while revision surgeries were mostly observed in the plate group (3 vs.  14).Within the plate group, the majority of revision surgeries were associated with Mason type III fractures when Mason type was reported; and (3) the available reports on safe zone definitions lack sufficient details to make conclusive decisions on the optimal placement of plates, as well as their impact on the ROM.Therefore, our findings suggest that functional outcomes for plate and screw fixation seem similar, regardless of influencing factors such as Mason type.For performing ADLs, both plate and screw fixation demonstrates adequate ROM for pronation.The screw group achieves sufficient supination, while the plate group lacks some degrees in this aspect.Both groups, however, show limitations in ROM with regards to flexion.

Differences in subgroups
To the best of the authors' knowledge, other reviews on this subject are not available.Therefore, outcomes found here cannot be compared to outcomes in other literature.According to Cote et al, 8 a high heterogeneity prevents us from performing statistical subgroup comparisons.This hampers interpretation of overall findings and hinders drawing definitive conclusions regarding the ROMs.
Certain factors that could impact the outcomes, such as complications affecting ROM and the type of plate used, were not taken into account in this review.Notably, plates mentioned in our review were AO miniplates, fracture-specific radial head locking plates, 2.0 mm conventional low-profile mini-T plates (Wego mini low-profile plate system, Wego, Weihai, China), and 2.4 mm locking compression plates (DePuy Synthes.Raynham, MA, USA), lowprofile T-plates (DePuy Synthes, Raynham, MA, USA) or undefined plate types.It is important to take these variations into account to understand the impact on the ROM fully.This review did not aim to emphasize subgroup differences but assessed the overall efficacy and safety of plates vs. screws.
Factors like HO, post traumatic elbow stiffness, ligamentous injury, and elbow dislocations were not discussed in this review due to inconsistent reports regarding inclusion and exclusion criteria.HO was not specified in all 13 articles that were included in this review.For post traumatic elbow stiffness, 10 articles did not specify either inclusion or exclusion, and 3 articles excluded patients with a limited ROM preoperatively.Ligamentous injury was included in 3 articles, excluded in 4 articles and unspecified in 6 articles.For elbow dislocations, 10 articles excluded these cases, while 3 articles did not specify either inclusion or exclusion.This hindered the ability to identify subgroups and evaluate the impact of these factors on ROM.Previous literature indicates that the abovementioned factors can limit elbow movement, 4,15,46,58 and the proper reporting of such factors is therefore important to contextualize the reported ROM.Ideally, a preoperative magnetic resonance imaging should be conducted alongside intraoperative testing to accurately map the extent of all injuries. 10econdly, several authors cite additional factors that could contribute to poorer functional outcomes related to plate fixation.These include pain, injury severity, plate size, and plate placement due to vascularization problems or scar tissue formation postoperatively, and accuracy of reported ROM, which can differ based on the methods used. 2,5,29,38Previous literature also suggests that kinesio-phobia and fear of reinjury influences ROM, while clinical and injury-related factors, with the exception of complications, show a weaker correlation with ROM. 24egarding complications, Bauer et al 3 identified risk factors for HO after ORIF procedure and found that time to first surgery and postoperative mobilization of the elbow are two possible risk factors.Plate fixation might take more time to surgery due to plate positioning, screw placement, plate adaptation and soft tissue handling, causing an increased risk for HO.Our study showed an incidence rate of 15/519 (3%) for HO, while exhibiting a slightly elevated incidence of HO in the plate group (11/248 [4%]), compared to the isolated screw group (4/271 [2%]) (Table III).However, screw fixation might take more time to mobilize due to a lack of stability, especially in the case of comminuted fractures.Both factors could play a big role in avoiding HO and need to be assessed more in future literature.
Lastly, as seen in practice, Mason fracture classification guides treatment choice according to the injury pattern. 23Higher Mason types, such as type III and IV, are more likely to be treated by ORIF with plates rather than screws, as demonstrated in our review.This could impact the outcome negatively as the resulting ROM, complications, and revision rates would not be solely decided by the ORIF technique but also by the severity and complexity of the fracture.Literature shows that a more severe Mason type usually correlates with a restricted ROM, 14 as well as a more ligamentous injury. 26,27mportantly, although numerous factors are described to affect ROM, our review reveals that regardless of these considerations, similar ROM outcomes are achieved for both plate and screw fixation.

Lack of safe-zone reports
Regarding safe-zone definition, only five of the thirteen studies reported a reproducible definition of the used safe zones for the placement of the hardware.The lack of sufficient details makes it impossible to derive conclusive decisions on the optimal placement of plates, as well as their impact on the ROM.With the limited available data, our findings suggest that plate placement on the anterolateral aspect or the posterolateral aspect of the radial head achieves a similar ROM for pronation.For supination, a slight increase of ROM (9 degrees) was observed when plates were positioned on the anterolateral aspect.However, due to substantial heterogeneity, no statistical analysis could be performed to confirm this.Additionally, a recent study by Ma et al 30 confirmed that functional scores decrease with plate fixation compared to screw fixation in cases where the fracture cannot be fixated within the safe zone.Conversely, fractures fixated within the safe zone exhibited no differences in outcomes between plate and screw fixation.
The literature describes different methods to identify and use this safe zone for the fixation of radial head and neck fractures.A cadaveric study by Caputo et al 7 determined the nonarticulating portion of the radial head and neck to ensure safe placement of internal fixation.In full supination, this was considered the posterolateral portion of the radial head, in which a thinner, more yellow cartilage was seen compared to the relatively wide and white cartilage of the articulating portion, indicating thinner hyaline cartilage.Palpation of the radial styloid and Lister's tubercle identified a safe zone of a 90 angle.Applying these anatomic landmarks to localize a safe zone may assist surgeons in fixating fractures of the radial head and neck without sacrificing ROM.Hoekzema et al 21 expanded on this method in their study, concluding that if a proximal radial head plate is placed 166 ± 10 opposite the bicipital tuberosity, the safe zone is still abided by.This landmark can be easily identified on intraoperative imaging. 21mith et al 48 propose a systematic approach by determining anterior and posterior limits for supination and pronation intraoperatively rather than relying on anatomical landmarks for safe zone identification. 48In contrast to plate fixation, hardware prominence is seldom seen in screw fixation, as screws can be buried within the radial head and neck. 39In conclusion, describing the utilized method of safe zone identification when fixating fractures with plates is important to facilitate future research on potential differences.

Limitations
There are also limitations in this review.While this study in part aimed to investigate the impact of plate fixation on ROM, it is crucial to address the presence of selection bias as a notable limitation.As mentioned previously, higher Mason type fractures are usually associated with ligamentous injury and an indication for plate placement.Our study also supported the first notion as plate fixation demonstrated a correlation with higher Mason type.However, our review shows that the mean degrees for ROM seem similar regardless of these factors.
Secondly, studies used within this review were primarily retrospective studies.This, in combination with the inherent bias and significant heterogeneity evident from calculated I 2 statistics, makes it difficult to draw firm conclusions.The origins of this heterogeneity observed within these studies remain unclear but could be explained by variability in study sample sizes and subjectivity of outcome measures.
Regarding the ROM, reported and measured flexion and extension are vastly different between articles depending on the experience of the observer and the tools used.Conventional clinical goniometry seems to be less accurate in estimating the ROM of the elbow compared to a trained human eye. 5Furthermore, extension is reported differently depending on the usage of either "extension" or "loss of extension", complicating general comparisons.
In reference to the safe-zone definitions, it is important to note that the verification of plate placement was not possible, and descriptions were gathered from the documented methodology.Consequently, caution is warranted in drawing definitive conclusions.

Future research
Acknowledging the identified limitation regarding selection bias, we propose that future research take the form of prospective studies.Specifically, we advocate for randomized controlled trials comparing screw and plate fixation to further investigate the influence on functional outcomes and the potentially enhanced effect of fracture types and plate fixation on this aspect.Randomized controlled trials also decrease chance of bias and heterogeneity, while comparability across studies can be increased through consistent methodology with respect to data collection, such as ROM measurements and choice of PROMs.
Secondly, it is not always safe to assume that all surgeons use the same safe zone.Therefore, we highly recommend explicitly documenting the safe zone within the methods or surgical techniques section to verify that all individuals follow the same procedure and to discover whether specific outcomes correlate to either technique or patient characteristics.This could be facilitated by implementing a national fracture database, similar to the Dutch database on radial head prostheses.

Conclusion
This review of predominantly retrospective studies suggests that the ROM seems similar for screw osteosynthesis and plate osteosynthesis of proximal radial fractures, despite the higher Mason types seen in patients treated with plate fixation.Other functional outcomes and complication rates showed similar results as well.Revisions were mostly observed within the plate group; however, the majority of revision surgeries were associated with Mason type III fractures when Mason type was reported.Due to high heterogeneity seen between the studies, statistical analysis was deemed inappropriate.
Finally, safe-zone definitions are rarely reported in literature and often lack sufficient details of operative techniques.This information is essential for gaining perspective on presented outcomes and making conclusive decisions about the optimal placement of plates and their impact on the ROM.

Figure 2 IncludedFigure 1
Figure2Fracture types categorized based on the Mason classification23,31 and segmented into plate and screw groups, presented as percentages.

Figure 3
Figure 3 Forest plots demonstrating outcomes per study, divided in groups, for postoperative supination (A), pronation (B), flexion (C), and loss of extension (D).Heterogeneity is depicted by I 2 per subgroup.Number, size of the study population, Mean, mean range of motion, SD, standard deviation, 95% CI, 95% confidence interval, I 2 , level of heterogeneity.a, conventional cortical screw group, b, headless compression screw group, c, novel group, d, conventional group, e, novel group, f, conventional group.The significant variability, potentially influenced by variying study sample sizes and subjectivity of outcome measures, should be taken into account when interpreting the overall findings.

Figure 4
Figure 4 Image depicting described safe zones for the anterolateral aspect (Yellow: Esser et al 14 & Li et al 29 ), posterolateral aspect (Green: Guo et al 17 & Yang et al 56 ) and combined aspect (Blue: Ma et al 30 ) of the radial head and neck.A, Anteriorl; L, Lateral; P, Posterior; M, Medial.
indicated screw fixation for Mason type I fractures with a mechanical block, Mason type II fractures, Mason type III fractures with 3 or less fragments, articular fractures, and extra-articular transverse radial neck fractures.Plate fixation was deemed appropriate in articles reporting on partial fractures, Table IV provides details of minor and major complications per group.The most common minor complications were mild pain (n ¼ 18), stiffness (n ¼ 17), and HO (n ¼ 15).The most common major complication was painful arthritis (n ¼ 12).Regarding revision surgeries, 2 patients underwent hardware removal in the screw group, and 1 patient underwent revision surgery for nonunion.Fourteen revisions took place in the plate group.Indications for revision surgery in the plate group were hardware removal (n ¼ 4), secondary displacement (n ¼ 4), nonunion (n ¼ 4), and hardware breakage (n ¼ 2).For the studies

Table I
Study characteristics & outcomes after open reduction internal fixation techniques for fractures of the proximal radius.reported Mason fracture types, revisions for hardware removal were seen in both Mason type II and Mason type III fractures, while all other revisions were solely attributed to Mason type III fractures. that

Table II
Outcomes per group for secondary postoperative outcomes.ORIF, open reduction internal fixation; No., number; 95% CI, 95% confidence interval; I 2 , Degree of heterogeneity within the specific group; MEPS, Mayo Elbow Performance Score; (Q)DASH, (Quick) Disabilities of Arm, Shoulder and Hand.

Table IV
Complication rates after open reduction internal fixation techniques for fractures of the proximal radius.